'Ripple' might be a powerful technique to fight a demon but it wasn't omnipotent. This technique is making similar energy similar to sunlight but of course, it is weaker than sunlight itself but it was enough to turn a demon into ashes.
It might be easy to fight a normal demon with 'Ripple' but it was different when it was used to fight Lower Moons, High Moons, and the progenitor of the demon itself.
Haru wasn't sure whether they could defeat the progenitor of the demon with a 'Ripple' technique but it was enough to make them become stronger. He felt a bit regretful since he didn't find the instructions of the 'Breath of Sun' since it had been lost in the past. He remembered in the story that Muzan was almost killed by the user of the 'Breath of Sun' but in the end, it was almost.
The user of the 'Breath of Sun' didn't kill him and they were killed instead.
Haru wanted to meet this boss of the demon as soon as possible then his Quest would be faster to end. He remembered that Muzan had turned into a demon because his doctor had used a Blue Spider Lily on him. He wondered whether that flower would grow after they had slain Muzan.
"..."
'That might be possible,' Haru thought inwardly.
They were on their way to the Natagumo Mountain to slay the demon that was living in that place. They were a bit complaining since the system didn't make any difference when they had killed the members of Lower Moons, High Moons demon, or the normal demon.
That was why they decided to come to this mountain since there were a lot of demons that were living in this location. They needed to slay 100 demons and they had only killed three demons after they had come to this world.
"..."
"That's the mountain," Shinobu said while pointing her finger.
They saw a large mountain with eerie air surrounding the locations.
Haru who had eaten 'Horo Horo no Mi' was quite surprised that there wasn't any evil spirit in that place. He might be thinking that it might be because of the existence of the demon that made there wasn't any evil spirit in this world.
The world will become unbalanced with the existence of both evil spirit and demon.
The humans in this world are too weak, even with their 'Breath Style' since it isn't that special compared to most of the techniques in another world.
Haru was wondering whether he might be fighting Thanos or Saitama in the future. He started to think that his power might not be enough to fight something that could make humans disappear with a snap of his fingers or defeat anything in one punch. He didn't really want to fight that monster and only wanted to live a comfortable life with his sister.
---
Mitsuri sighed when she thought that she couldn't follow them.
"What's wrong, Mitsuri?" Rengoku asked.
"I wonder whether they're single," Mitsuri asked.
"Who? Korosensei?" Rengoku asked.
"Of course not, I mean both Kasugano-san and Sakata-san," Mitsuri said.
"Well, you should try it and ask them whether they're single or not, they will go back later after they have slain the demon," Rengoku said.
They had known their power since they had spent most of their time training together with them. They knew that they were very powerful, especially the bipedal octopus. They had been harassed by that octopus for the past week and wanted to have revenge but it was impossible to do that.
Gintoki might be the weakest but his strength also couldn't be underestimated. Even Gyoumei, who was known as the strongest Pillar, couldn't beat Gintoki in terms of strength.
Haru was the most mysterious of all of them since it was impossible to hit or punch him. They weren't sure but it seemed that this guy could read the future. His technique was also very bizarre and it was hard to read him.
They were sure that they would be massacred once three of them had become serious but they had never seen them become serious since most of them were often pranking them, eating sweets, or sleeping.
"...."
"Mitsuri, I think the two of them have someone already," Obanai said.
"Eh? Really? How did you know?" Mitsuri asked.
Obanai Iguro is a Demon Slayer and the Snake Pillar of the Demon Slaying Corps. He is a young man with black hair that has bandages warped around his mouth and has a snake that wraps itself around his neck. He has a secret that he loves Mitsuri and he doesn't want her to get close to three of them.
"First that Sakata is quite old, he might have a wife in his country," Obanai said.
"That's true," Mitsuri nodded.
"And lastly, that Kasugano might have done it with Shinobu," Obanai said.
"..."
"What?!" Everyone was startled when they heard it.
"Do you think so too?" Mitsuri asked. She also realized that the relationship between Shinobu and Haru were very close and their fight was something that was similar to a flirt.
Obanai nodded, "Yes, that's why you should give up and support Shinobu."
Mitsuri sighed and nodded, "Alright, I'll support her." She had become spirited and would support her friend to gain her love.
Obanai nodded in satisfaction.
---
"Achoo!" Shinobu sneezed suddenly before entering the mountain.
"What's wrong? Are you cold?" Haru asked.
"No, there is nothing," Shinobu shook her head. She was wondering whether someone was talking about her since she had gotten very annoyed.
"So let's go," Haru said.
They entered the mountain together and wanted to slay the entire demon in this mountain.
---
"There is a group of people who have entered our home."
They nodded and didn't say anything since someone had entered their home then their fate had been decided and that was to become their family's food.